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Study of behavior of concrete and cement based composite materials exposed to high temperatures
Bodnárová, L. ; Horák, D. ; Válek, J. ; Hela, R. ; Sitek, Libor
The paper describes possibilities of observation of behaviour of concrete and cement based composite material exposed to high temperatures. Nowadays, for large-scale tests of behaviour of concrete exposed to high temperatures, testing devices of certified fire testing stations in the Czech Republic and surrounding states are used. These tests are quite expensive. For experimental verification of smaller test specimens, a testing device was built at the Technical University in Brno, where tests of thermal loading of concrete tests specimens of various sizes can be carried out (dimensions up to 800 x 800 x 800 mm or slabs up to 1100 mm of length). The testing device opens new ways of observation of behaviour of concrete and cement based composite materials exposed to high temperatures as well as preparation of specimens for observation of interaction of water jet and concrete degraded by action of high temperatures.
Fulltext: content.csg -  DOC
Plný tet: UGN_0398264 - DOC
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Migration to selected EU countries: Labor market integration
Kaclíková, Roberta ; Šaroch, Stanislav (advisor) ; Němcová, Ingeborg (referee)
The aim of this master thesis is to analyse the labor market of European Union and its certain countries in relation to the immigration with the backgound of various social welfare models. The paper is analysing the topic of labor market of European Union, integration of immigrants on this market, with focus on economies and labour markets of Sweden, United Kingdom and Germany as countries with high level of immigration that are representing three different social welfare models, such as Nordic model, Liberal model and Conservative model. The main objective of this thesis is the analysis of labor markets in selected countries of the European Union in relation to immigration and their subsequent comparison using the background of different social welfare models. The result is the evaluation of effectivness of the various social models based on statistical data, acquired knowledge and performed comparisons. The thesis is divided into four chapters and contains 13 tables and 8 charts.
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ELECTRON BEAM REMELTING OF PLASMA SPRAYED ALUMINA COATINGS
Matějíček, Jiří ; Veverka, J. ; Čížek, J. ; Kouřil, J.
Plasma sprayed alumina coatings find numerous applications in various fields, where they enhance the properties of the base material. Examples include thermal barriers, wear resistance, electrical insulation, and diffusion and corrosion barriers. A typical structure of plasma sprayed coatings, containing a multitude of voids and imperfectly bonded interfaces, gives them unique properties - particularly low thermal conductivity, high strain tolerance, etc. However, for certain applications such as permeation barriers or wear resistance, these voids may be detrimental.\nThis paper reports on the first experiments with remelting of plasma sprayed alumina coatings by electron beam technology, with the purpose of densifying the coatings and thereby eliminating the voids. Throughout the study, several parameters of the e-beam device were varied - beam current, traverse velocity and number of passes. The treated coatings were observed by light and electron microscopy and the thickness, structure and surface morphology of the remelted layer were determined and correlated with the process parameters. Based on the first series of experiments, the e-beam settings leading to dense and smooth remelted layer of sufficient thickness were obtained. In this layer, a change of phase composition and a marked increase in hardness were observed.\n
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Sorption and Stabilization of Metals/Mettalloids by Innovative Synthesized Sorbent Amochar.
Ouředníček, P. ; Trakal, L. ; Komárek, M. ; Pohořelý, Michael
Remediation of contaminated soil which is based on stabilization and immobilization of potential\nhazardous substance by sorption materials has been studied intensively nowadays. Biochar – activated organic carbon belongs to this group of stabilizing agents which can adsorb wide range of contaminants, including metals/metalloids. Surface area of the biochars is quite large in general and functional groups (e.g. COO–) can form chelates or alkaline elements on the surface, which is represented by cation exchange capacity. Altogether with the high pH values (7.00 – 10.00), biochars are quite effective sorbents and can adsorb metals/metalloids from the solution (ground water), especially in acidic soils (in the environments affected by intensive mining activities). Sorption\neffectiveness can be increased (especially for As (V) or Cr (VI) sorption) by modification of biochar by various types of secondary oxides. Innovative sorbent AMOchar (AMO + biochar) has been synthesized currently. The product was prepared by adding of biochar to the reaction solution during amorphous manganese oxide (AMO) synthesis. The AMOchar was formed mainly by Mn-oxalates which had coated surface of the pristine biochar. AMOchar composite was able to remove significantly higher amounts of various metal(loid)s from the solution despite the rather high pH of the material. Sorption effectiveness was high not only in case of Pb (II) sorption (almost 99%), and Cd(II) (51.2%), but also a very high amount of As(V), 91.4%. Additionally, both AMOchar composite was able to reduce Mn leaching. This can avoid potential post-contamination caused by the dissolution of less stable Mn-oxalates as observed in the pure AMO.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_22316111113040 - PDF
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Nutritional analysis and optimization of breeding of selected species of edible insects under conditions of the Czech Republic with regard to human health
Adámková, Anna ; Kouřimská, Lenka (advisor)
All over the world, the edible insects are considered a highly nutritious food with high protein and fat content. However, the nutritional value of insect is not constant. It can be affected by species, developmental stage, rearing technology or nutrition.
Therefore, this thesis was aimed at obtaining the selected nutritional value of edible insects. Analyses were focused on the determination of the crude protein content, fat content, fatty acid profile and sterols in selected species of edible insects, which can be commonly reared in the Czech Republic. At the same time we also analysed samples of insects reared on the island of Sumatra to evaluate the influence of the climate on the nutritional value. The main aim of the thesis was the determination of optimal breeding conditions, developmental stages and feed rations for obtaining good production of insects with nutritional properties suitable for human nutrition. The analyses showed a high nutritional value of selected insect species, but also confirmed the significant differences in the content of individual nutrients between different species depending on the climate conditions and developmental stage. Comparing the fat and crude protein content in edible insects and other conventional sources of meat it has been found, that the examined insect is similar to beef concerning the fat and crude protein content. The results obtained are the basis for determining the appropriate rearing conditions and developmental stages for obtaining insect with the desired nutritional properties for human nutrition.
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The use of biomass ash
Ochecová, Pavla ; Tlustoš, Pavel (advisor) ; Radim, Radim (referee)
One of the most frequently used sources of renewable energy is biomass, mainly wood biomass. Incineration is the most common technology utilizing the energy from biomass to produce heat. A byproduct of these technologies is ash, whose composition depends on the feedstock composition and the incineration technologies. Due to the high content of valuable nutrients in ash, one of the suitable option for ash utilization seems to be application into agricultural or forestry land. Therefore, it is necessary to test response of soils and plants and look for the most suitable combination of soil additive (biomass ash), and plants. Experimental part of PhD thesis was divided into the incubation experiment and the vegetation pot experiments. The incubation experiment: The efficiency of ash addition at two application rates was tested for nutrients enrichment in different soils within period of 56 days. The vegetation pot experiments: The two plants Triticum aestivum L: (three-year experiment) and Lolium perenne L. (one-year experiment) were planted in the 5L pots. Soils were treated with ash or ash combinated by superphoshate and flue gas desulfurization gypsum. For both plants, we evaluated the plant growth, biomass production and content of macro, micro and toxic elements in the biomass and in the soils.
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Exploitation of GPU in graphics and image processing algorithms
Jošth, Radovan ; Svoboda, David (referee) ; Trajtel,, Ľudovít (referee) ; Herout, Adam (advisor)
Táto práca popisuje niekoľko vybraných algoritmov, ktoré boli primárne vyvinuté pre CPU procesory, avšak vzhľadom k vysokému dopytu po ich vylepšeniach sme sa rozhodli ich využiť v prospech GPGPU (procesorov grafického adaptéra). Modifikácia týchto algoritmov bola zároveň cieľom nášho výskumu, ktorý bol prevedený pomocou CUDA rozhrania. Práca je členená podľa troch skupín algoritmov, ktorým sme sa venovali: detekcia objektov v reálnom čase, spektrálna analýza obrazu a detekcia čiar v reálnom čase. Pre výskum detekcie objektov v reálnom čase sme zvolili použitie LRD a LRP funkcií. Výskum spektrálnej analýzy obrazu bol prevedný pomocou PCA a NTF algoritmov. Pre potreby skúmania detekcie čiar v reálnom čase sme používali dva rôzne spôsoby modifikovanej akumulačnej schémy Houghovej transformácie. Pred samotnou časťou práce venujúcej sa konkrétnym algoritmom a predmetu skúmania, je v úvodných kapitolách, hneď po kapitole ozrejmujúcej dôvody skúmania vybranej problematiky, stručný prehľad architektúry GPU a GPGPU. Záverečné kapitoly sú zamerané na konkretizovanie vlastného prínosu autora, jeho zameranie, dosiahnuté výsledky a zvolený prístup k ich dosiahnutiu. Súčasťou výsledkov je niekoľko vyvinutých produktov.
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Generic Reverse Compilation to Recognize Specific Behavior
Ďurfina, Lukáš ; Šaloun, Petr (referee) ; Zahradnický,, Tomáš (referee) ; Kolář, Dušan (advisor)
Práce je zaměřena na rozpoznávání specifického chování pomocí generického zpětného překladu. Generický zpětný překlad je proces, který transformuje spustitelné soubory z různých architektur a formátů objektových souborů na stejný jazyk na vysoké úrovni. Tento proces se vztahuje k nástroji Lissom Decompiler. Pro účely rozpoznání chování práce zavádí Language for Decompilation -- LfD. LfD představuje jednoduchý imperativní jazyk, který je vhodný pro srovnávaní. Konkrétní chování je dáno známým spustitelným souborem (např. malware) a rozpoznání se provádí jako najítí poměru podobnosti s jiným neznámým spustitelným souborem. Tento poměr podobnosti je vypočítán nástrojem LfDComparator, který zpracovává dva vstupy v LfD a rozhoduje o jejich podobnosti.
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Security of Contactless Smart Card Protocols
Henzl, Martin ; Rosa, Tomáš (referee) ; Staudek, Jan (referee) ; Hanáček, Petr (advisor)
Tato práce analyzuje hrozby pro protokoly využívající bezkontaktní čipové karty a představuje metodu pro poloautomatické hledání zranitelností v takových protokolech pomocí model checkingu. Návrh a implementace bezpečných aplikací jsou obtížné úkoly, i když je použit bezpečný hardware. Specifikace na vysoké úrovni abstrakce může vést k různým implementacím. Je důležité používat čipovou kartu správně, nevhodná implementace protokolu může přinést zranitelnosti, i když je protokol sám o sobě bezpečný. Cílem této práce je poskytnout metodu, která může být využita vývojáři protokolů k vytvoření modelu libovolné čipové karty, se zaměřením na bezkontaktní čipové karty, k vytvoření modelu protokolu a k použití model checkingu pro nalezení útoků v tomto modelu. Útok může být následně proveden a pokud není úspěšný, model je upraven pro další běh model checkingu. Pro formální verifikaci byla použita platforma AVANTSSAR, modely jsou psány v jazyce ASLan++. Jsou poskytnuty příklady pro demonstraci použitelnosti navrhované metody. Tato metoda byla použita k nalezení slabiny bezkontaktní čipové karty Mifare DESFire. Tato práce se dále zabývá hrozbami, které není možné pokrýt navrhovanou metodou, jako jsou útoky relay.
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